if( document.images )
    {
    map1 = new Image(356,270) ;
    map1.src = "images/map1c-1.gif";
    map2 = new Image(356,270) ;
    map2.src = "images/map1c-2.gif";
    map3 = new Image(356,270) ;
    map3.src = "images/map1c-3.gif";
    }

function chkver(imagename,objectsrc)
    {
    var n=navigator.appName
    var v=parseInt(navigator.appVersion)
    var browsok=((n=="Netscape")&&(v>=3))
    var browsok2=((n=="Microsoft Internet Explorer")&&(v>=4))
    if ((browsok)||(browsok2))
    document.images[imagename].src=eval(objectsrc+".src")
    }